[CMake] Installing Python Modules with CMake

[Michael Wild]

On 01/03/2011 09:11 AM, Todd Gamblin wrote:
> Is there some standard way in CMake to get a project-local install destination for python libraries, e.g.:
> 
> 	${CMAKE_INSTALL_PREFIX}/lib/python2.6/site-packages
> 
> Is this something find modules typically provide?  I can construct this name easily enough myself, but it involves querying the python executable for its version then regexing that string, and I feel like FindPythonLibs should do stuff like that for me.  It would be nice to have something called, say, "CMAKE_PYTHON_INSTALL_PREFIX" set to this path in advance, so that I can just install python modules there.
> 
> Or am I missing something?  I couldn't fund much on installing python files in the docs.
> 
> -Todd
> 

I think you'll have to query Python yourself. Of course, this becomes
difficult if you're cross-compiling, in which case you would need to
parse the <prefix>/lib/pythonX.Y/config/Makefile file yourself and fetch
all the relevant variables (datarootdir, BINDIR, DESTSHARED, LIBDEST,
etc.) and then ask the user what prefix and exec_prefix he wants
(presumably CMAKE_INSTALL_PREFIX maps to prefix, and usually exec_prefix
is the same as prefix, but that's not always the case). Not sure how
that works on Windows, though...

I wouldn't rely too much on FindPythonLibs. The whole FindPython* is a
sorry mess (IMHO) and needs some serious overhaul, but that is some
major undertaking an apparently the suffering wasn't big enough so far
for somebody to take action...

Michael